we would like to habe a node type only for side wide available values. We think we have a title and a 'value' field. When we need one of these values in text areas/fields we would like to type [title_of_the_node] and in the output we get the value of the value field displayed.
Does anyone know a solution for this?
Have you looked at the Token API? With the API one can define custom tokens. The functions you should look at are:
With hook_token_info() you define new tokens. In your case you could retrieve all nodes of your configureation node type (with an EntityFieldQuery for example), loop over the entries and create a token for each of them.
In hook tokens you define what your tokens are replaced with - just load the node entity for the given token and retrieve the content of your value field.
Here is a tutorial I found useful when writing some custom tokens a while back: http://www.fredparke.com/blog/create-your-own-tokens-drupal-7
